package com.itheima.reggie.controller;


import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.UUID;

//文件上传和下载
@RestController
@Slf4j
@RequestMapping("/common")
public class  CommonController {

    @Value("${reggie.path}")
    private String basePath;


    @PostMapping("/upload")
    public R<String> upload(MultipartFile file){
        //file是一个临时文件，需要转存到指定位置，否则请求结束后就会被删除
        log.info(file.toString());

        //原始文件名
        String originalFilename=file.getOriginalFilename();//abc.jpg
        String suffix=originalFilename.substring(originalFilename.lastIndexOf("."));

        //使用UUID重新生成文件名，防止为简明重复造成文件覆盖
        String fileName=UUID.randomUUID().toString()+suffix;//adffffff.jpg

        //创建一个目录对象
        File dir=new File(basePath);
        if(!dir.exists()){
            dir.mkdirs();
        }

        try {
            //将临时文件转存到指定位置
            file.transferTo(new File(basePath+fileName));
        } catch (IOException e) {
            e.printStackTrace();
        }
        return R.success(fileName);
    }

    @GetMapping("/download")
    public void download(String name, HttpServletResponse response){

        try {
            //输入流，通过输入流读取文件内容
            FileInputStream fileInputStream=new FileInputStream(new File(basePath+name));

            //输出流，通过输出流将文件写回浏览器，在浏览器展示图片
            ServletOutputStream outputStream=response.getOutputStream();

            response.setContentType("image/jpeg");

            int len=0;
            byte[] bytes=new byte[1024];
            while ((len = fileInputStream.read(bytes)) != -1){
                outputStream.write(bytes,0,len);
                outputStream.flush();
            }

            outputStream.close();
            fileInputStream.close();


        } catch (Exception e) {
            e.printStackTrace();
        }




    }
}
